Thermodynamic and spectroscopic measurements of the electron-hole drop binding energy in Ge: An old problem revisited

One can expect to get the electron-hole (EHD) binding energy φ either from spectroscopic or from threshold measurements. While the value obtained by the former is in excellent agreement with theory, the results given by the latter did not seem to lead to φ in a simple way. We present here new optical threshold studies in which we think that the right conditions to obtain a direct thermodynamic measurement of φ have been mastered. Besides, our results present novel features like a sharp jump of the EHD luminescence at threshold above 2.4 K and observation of hysteresis in the whole temperature range of our work.     

Pulmonary effects of chronic exposure to airborne cadmium

In haemoglobinometry grave errors are still being made even though an internationally accepted standardized method is available for the determination of the haemoglobin content of blood. Up to the present only haemiglobincyanide reference solutions have been available on a wide scale to check the measuring stage of the standardized haemiglobincyanide method. These reference solutions are shown to remain stable, under proper storage conditions, for more than 10 years. Concentrated haemoglobin solutions have become available recently, offering the possibility to control the dilution and conversion steps of the haemiglobincyanide method. Such a solution is shown to remain stable, under proper storage conditions, for at least a year. Using both haemiglobincyanide reference solutions and concentrated haemoglobin solutions, as well as having the possibility of checking the cyanide content of the reagent used, an acceptable intra-laboratory control program may now be set up.     

Polyvinylpyrrolidone-storage disease. Light microscopical, ultrastructural and chemical verification

The light and electron microscopical findings in the polyvinylpyrrolidine-storage disease are reported on the basis of biopsies of skin, striated muscle, bone marrow and liver from one patient and a subcutaneous nodule from another patient. Both patients suffer from diabetes insipidus and have been treated for several years with Insipidin retard, which contains polyvinylpyrrolidone (PVP) as the retarding agent. Deposits of PVP have been demonstrated in all the tissues examined and can easily be recognized by certain staining qualities. The combination of haematoxylin-eosin, elastin (Weigert), alkaline Congo red and Sirius red for amyloid and PTAH is specially to be recommended. The ultrastructural findings consist of intracellular vacuoles containing a granular material and probably representing lysosomes. The final identification of the nature of the deposits has been made by spectrophotometric analysis. The suspicion of a case of PVP-storage disease should result in a skin biopsy which usually is sufficient for the diagnosis.     

Inactivation of Semliki Forest Virus in aerosols

Purified Semliki forest virus in aerosols is inactivated rapidly at 40% and above 70% relative humidity. At all humidities tested the decay of virus infectivity runs parallel with the decrease in hemagglutination activity, whereas the biological integrity of the virus ribonucleic acid is preserved. Also, free infectious ribonucleic acid is stable after spraying at all relative humidities. Evidence is presented for the hypothesis that above 20% relative humidity, virus inactivation in aersols is mainly due to surface-dependent factors, damaging the virus coat.     

Chances of reducing the formation of immune antibodies after massive transfusions in open heart surgery (author's transl)

Children, young people and women at the age of possible maternity form the majority of patients operated by extracorporal circulation. A longterm planning of these operations should also have donor in call, who are compatible with the patients' Rh groups and Kell antigens. Having practiced such a selection of donors we succeeded in reducing the formation of immune antibodies. 6 out of 330 patients had antibodies, but 4 had been sensibilized before operation. In the case of the other 2 it would not be excluded that they might have been immunized a long time ago. We emphasize the importance of hemodilution, strict indication of every postoperative therapy with red cells and the autologous transfusion.     

Nanosecond-pulse fluorimetry of wheat-germ agglutinin (lectin)

Nanosecond-pulse fluorimetry of wheat germ agglutinin is analyzed as a function of both excitation and emission wavelengths. When excited at 280 nm, wheat germ agglutinin fluorescence exhibited three lifetimes: one corresponding to the tyrosine residues as a whole and two others corresponding to the tryptophyl emission. The tyrosine contribution to the emission spectrum deduced from this method was in good agreement with that reported previously in steady-state fluorescence experiments [Privat, J.P. and Monsigny, M. (1975) Eur. J. Biochem. 60, 555-567]. The fluorescence decay of each tryptophan residue was not a single exponential function when wheat germ agglutinin was excited at 295 nm. This could be related to the microenvironment of the indole chromophores in the protein. The comparison of the quantum yield and of average lifetime showed that some tryptophan residues were completely quenched. Energy transfer from tyrosines to tryptophan residues previously detected in steady-state fluorescence was also revealed by fluorescence decay measurements. Comparison of both methods showed that an important part of transfers occurred with a very fast rate equal to or greater than 10(10) s-1. Both lifetimes and the ratio of the short and the long-lived component were found dependent on tri-N-acetylchitotriose binding.     

Surgical treatment of renovascular hypertension

Two hundred sixty-four patients exhibiting renal artery occlusive disease underwent operation for renovascular hypertension between 1961 and 1977. Included were 27 pediatric patients. Fibrodysplastic disease affected 132 adults. Atherosclerotic lesions affected 51 patients with and 54 patients without clinically overt extrarenal arteriosclerotic cardiovascular disease. Ischemic kidney renin hypersecretion (renal: systemic index greater than 0.48), associated with suppressed contralateral kidney renin secretion (renal: systemic index approaching 0.0) predicted curability most reliably. Three hundred forty-eight operations were performed, of which 297 were primary and 51 were secondary procedures. Nephrectomy was initial therapy in 15 cases. Three operative deaths occurred among 51 patients manifesting overt extrarenal arteriosclerotic disease. No operative mortality was encountered among the other 213 patients. Surgical benefits were afforded 96% of pediatric patients and adults with fibrodysplastic disease, 91% of patients with focal renal arteriosclerosis, and 73% of those exhibiting overt extrarenal arteriosclerosis.     

Punctate pressure sensitivity: effects of skin temperature

The dependence on skin temperature of tactile sensitivity to punctiform (hair) stimulation of the finger tip came under study in five subjects. Their data show that punctate sensitivity is relatively stable over a wide range of thermal environments. On the average, some elevation of touch threshold occurred at a skin temperature of 20 degrees C (i.e., about 10 degree below normal), but severe loss of sensitivity first occurred at 10 degrees C. A small but possibly insignificant loss appeared at skin temperatures of 40 and 43 degrees C. The relatively stable behavior of the punctate threshold between about 20 and 40 degrees C contrasts with that of the vibrotactile threshold, which, at least for high frequencies, depends strongly on the skin temperature.